Magnetic separating apparatus



C G. BUQHANAN.

. MAGNETIC SEPARATING APPARATUS.

APPLICATION HLED JUME12. 191s.

v 6 I W 4&4. f 60 PATENTTOFFTICE.

uNirEo STATES CHARLES GORDON BUCHANAN", 01F ROSEVILLE, NEW JERSEY.

MAGNETIC SEIEMATING- APPARATUS.

V v Specification of Letters Itatexit. Patented J an, 18, 1921Application med June 12, 1915. Serial N'o. 239,516.

. To all w/tom it may concern:

Be it known that I, Crranrns BU- UECANfiiN, a citizen of the UnitedStates, residing at l ioseville 1n the county oi ldissex and State ofNew Jersey, have invented cer tain new and useful Improvements 1n Magiletic Separating Apparatus, out which the following is a specification.

p This inventioiijrelates to magnetlc separators and particularly tothat typeof-separator wherein the material is carried over a rotarymagnetic cylinder or pulley The object of the invention is to make thispulley cheap in construction and assembly,

readily variable in length, and easily re: paired. l Vith this in viewthe pulley is formed to be built up oi a series of dupli cate sectionsassembled by simply shppmg them together on the shaft and interlockedbyvthcir interengagements into a rigid unlt. Difi'erentilengthsoiipulley are easily made by varying the number or sections assem bledand for each size 1n diameter onlyv one set of standard parts have to bemanufactured or carried in stock. I

A further object of the invention is to arrange the magnet windings ofthe pulley sections to produce the same strength of magnetism so thatthere is attamed a uniform selective action on the material throughoutthe entire holding surface.

111 the accompanyin drawings, Figure l is a plan View of apparatus em-'bodying this invention Fig. 2 is a side elevation of the same; I

Fig. 3 is a central sectional View of a mag netic pulley censtructed inaccordance with this invention;

Fig. at is a central section of the conductor rm 3' ig 5 is a view insection of certain of the pulley elements detached, and

Fig. 6 is a central sectional View of amodified form of magnetic pulley.

In the specific embodiment of the inven tion shown in the drawings, 1 isan endless belt traveling around the idler. pulley 2 and the drivingpulley 3, within which are solenoid windings producing a magnet c fluxat the periphery. The material, .from which magnetic particles are to beseparated, is fed onto the upper surface of the belt and carried therebyto the cylinder 3, which attracts the metallic or magnetic particles andholds themagainst the belt while the rest of ing magnetic ores fromthe1r ganguefautkis thematerial as it passes down overthe ylinderdrops'pfl" and-is discharged by 'grav-= ity down the chute i, themagnetic material is retained and carried on and later dropped off intochute 5 as the further movement of the belt increascs the gravityefie'ct on the particles and decreases the magnetic attraction. Suchapparatus is useful in separatparticularly useful in removing bits ofsuch as broken drill points, pick pointsyan'd so forth from various ores.to prevent eiicessive wear or breakage of the fine grinding machineryemployed in the treatment of these minerals, also. in separating trampiron from coal, used as pulverized fuel. re-- quiring veryfine grinding;and for extractscrap from bone-black, used in sugar re memes. i

In theapparatus shown, the endless belt 1 may be 01 any desired lengthand may itself serve as aconveyer. The idler pulley 2 is adjustabletotake up slack and the magnetic pulley 3 has its shaft 6 provided with,

drlving means at 7. The other endof the shaft 6 carries the conductorcontact rings 8 and 9 for receiving the current from the brushes 10 ofopposite terminals and the shaft is hollowed out or drilled tc form apassageway 11 (see Fig. 8) for the wires from these rings to carry thecurrent to thesolenoids mounted within the pulley.

The roll 3 is built up of a series of standard, interchangeable sectionskeyed to the shaft 6 and ti htly drawn together by the tie rods 15. fthese sections the solenoid spools 16 of magnetic" material, preferablysteel, carry the magnet coils 17, adjacent through the metal particleson the surface of the belt. These rings 18 complete the periphery of thepulley between the spool flanges and are formed to be assembled on andinterlock With the spools. Each spool 16 has a large flange 20 and asmall flange 21 permitting the spacer ring 18 to slide over (see Fig. 5)into engagement with the large flange which has a ledge 22 to receiveand center it while the other end 23 of the ring remains partiallyseated on the smaller flange 21.

The large flange 20 of each spool is re CQSSGd as at 24 to receive thesmaller flange of the adjacent spool and abut against the correspondingring 18 so that the latter is held snugly in place between the spoolflanges. For economy and lightness each ring 18 is channeled in crosssection and provided with the stiffening ribs 25 and, in order tointerlock the parts against relative rotation, the rings 18 carry dowelstuds 26 engaging in holes 27 in the spool flanges 20. The spools andrings are easily assembled by simple axial movement (see Fig. 5) andpositioned on the shaft 6 and fastened together by the tierods'li'ibetween the end plates 30 and 31 corresponding respectively to thelarger and smaller spool flanges 20 and 21. In order to prevent thematerial from being drawn onto the magnetized end flanges where it wouldaccumulate in an objectionable manner the belt is preferably wide enoughto overhang these flanges; and end rings 32 of brass or othernon-magnetic material are provided for this overhang of the belt to runon.

In the construction shown in full lines in'Figs. 3 and 5, each coil 17is a continuous winding in one direction and adjacent coils are wound inopposite directions so that the magnetic flux is forced outward not onlyat the ends, but also passes througi'i the spool flanges to theperiphery of the pulley at a plurality of intermediate sections a seriesof gaps along the periphery. in this form it is best to have an evennumber of gaps, otherwise there would be what is termed a bucking coil.For instance, if a three gap pulley were made instead of a four as shownin the drawing there would 'be two coils having a right-hand directionand one a left-hand direction, or vice versa. With an even number ofcoils this is fairly balanced, but the end pieces of course are weakerthan the center magnets owin to the fact that there is no wire orwindings on the outside. To compensate for this relative weakening ofthe end pieces end coil 40,2114 indicated in dotted lines in Fig. 3,-

may be added on hubs of plates 30, 31 at' each end of the pulley andheld in place by disks 41 ot-non-magnetic material. coils will be Woundin a direction opposite to that of the adjacent coils to increase theflux through the magnetic end pieces while the end rings 32 and disks 41of brass will distribute the return flux through the extreme end poles.

forming beyond the periphery of These In order to make the distributionof the flux more uniform and extended and pro duce a constructionwherein there will be an even number olcoils irrespe tive of the numberof sections. the construction shown in Fig. 6 ma y be resorted to. Hereeach of the center coils 1T broken up into two oppositely wound sectionsas indicated by the arrows in said figure. Each end piece 30 and 31carries a half coil section 37 adapted to increase the magnetic strengthat the ends of the policy so as to give a sub stantially uniform holdingpower through out the periphery. Th 1 absence of magnetic materialbetween the adjacent sections oi the coils also "forces the magneticflux through paths farther out from the periphery of the pulley so thata thicker layer of material'on the belt will be properly magnetized. Endrings 32:" and disks 11 house the end coil sections and are preferablyof brass or other nouunagnctic material so that the flux of the extremeend pole is well distributed and the material will not gather andaccumulate upon the ends of the pulley.

The apparatus of this invention is sim dc to manufacture and low incost. Zach different width of pulley is built up by :sseinbling therequired number of' duplicate sections which are cheaply produced inquantity, reduce the number of dill'ercut parts that have to be kept instock. and permit the pulley to be quickly taken apart and repaired.Each section is rigidly fastened to the other and keyed to the shaft sothat ample space is provided for the solenoid windings permitting alarger number oi ampere turns and a larger quantity of wire with a.corresponding low amperage so that there will be insured an 000110111)oi. current, a minimum degree of temperature in the wire, and long lifeto the coils.

It is obvious that various modifications may be made without departingfrom the principle of the invention which is not confined to thespecific embodiments shown or described, but is intended to cover suchmodifications thereof as fall within the scope of the appended claims.

Having thus described my invention, I declare that what I claim as newand desire to secure by Letters Patent, is

1. A magnetic pulley comprising a winding supported between llangesextending said coil, and a spacer ring bridging said flanges, saidspacer ring being channeled in section. with inwardly directed edgesengaging said flanges and an outer surface forming the periphery of saidpulley.

2. 'magnetic pulley comprising a shaft, a plurality of dupli atemagnetic sections adapted to be each directly and independpendentlysupported on said" -inagnetic spool sections each havin ently siipportedon said shaft to form the pulley, each section comprising a coil spoolof magnetic material having a large flange extending to the periphery ofthe pulley,

and a small flange adapted to engage the large flange of the nextadjacent spool in assembled position. i

A magnetic pulley comprising a shaft,

a plurality of duplicate magnetic sections .tlangeof the next adjacentspool in'assemhled position, and a spacer ring intervening betweensuccessive large. flanges.

- 4. In a magnetic pulley the combination with a shaft, of a pluralityof duplicate inte gral flanges at each end directly an indeshaft, eachspool having a separate winding thereon and rings bridging the endflanges of said spools, and having circular-peripheries at the beltsurface of said pulley.

5. A magnetic pulley comprising a series of coil spools, at least one.of said spools having directly adjoining coils of opposite polaritythereon; l a v 6. A. magnetic pulley comprising a series of coil spools,at least one of said spools having directly adjoining coils of oppositepolarity thereon, and a single end coil of polarity opposite to that ofthe adjacent intermediate coil.

7. In a magnetic pulley, a pair of coils of opposite polarity, means atthe adjacent ends of said coils providing a path of. low permeability tothe abutting fluxes, and means at the o posite ends of said coils forcompleting t 'e magnetic circuit so that the flux at the periphery ofthe pulle will be forced outwardand evenly distri uted,

8. In a magnetic pulley, a series of coils v of alternately differentpolarity, means pro-. viding magnetic paths of high permeability betweenalternate adjacent ends of coils of opposite polarity, and meansproviding ma neticpaths of relatively low )erme abi ity between theintermediate a jacent ends of said coils, so that the abutting fluxesthereat will be spread and the flux at the periphery of the pulley willbe evenly distyibuted. s v

CHARLES GORDON BUCHANAN.

